Wireless mobile communication technology uses various standards and protocols to transmit data between a node (e.g., a transmission station) and a wireless device (e.g., a mobile device). Some wireless devices communicate using orthogonal frequency-division multiple access (OFDMA) in a downlink (DL) transmission and single carrier frequency division multiple access (SC-FDMA) in an uplink (UL) transmission. Standards and protocols that use orthogonal frequency-division multiplexing (OFDM) for signal transmission include the third generation partnership project (3GPP) long term evolution (LTE), the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard (e.g., 802.16e, 802.16m), which is commonly known to industry groups as WiMAX (Worldwide interoperability for Microwave Access), and the IEEE 802.11 standard, which is commonly known to industry groups as WiFi.
In 3GPP radio access network (RAN) LTE systems, the node can be a combination of Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node Bs (also commonly denoted as evolved Node Bs, enhanced Node Bs, eNodeBs, or eNBs) and Radio Network Controllers (RNCs), which communicates with the wireless device, known as a user equipment (UE). The downlink (DL) transmission can be a communication from the node (e.g., eNodeB) to the wireless device (e.g., UE), and the uplink (UL) transmission can be a communication from the wireless device to the node.
In computer networking and/or wireless communication, different functions can be provided by different layers in a protocol stack. The protocol stack (PS) can be an implementation of a computer networking protocol suite. The protocol stack (or protocol suite) can include the definition and implementation of the protocols. Each layer or protocol in the protocol stack can provide a specified function. The modularization of the layers and protocols can make design and evaluation of the computer networking and/or wireless communication easier. In an example, each protocol module or layer module in a stack of protocols may communicate with at least two other modules (e.g., a higher layer and a lower layer). The lowest protocol or layer can provide low-level, physical interaction with the hardware. Each higher layer may add more features. The upper or topmost layers can include user applications and services.
In the LTE system, communication layers can include a physical (PHY) (i.e., layer 1 (L1)), a data link (i.e., layer 2 (L2)), a network (i.e., layer 3 (L3)), and an application layer. In an example, layer 2 (L2) can include media access control (MAC), radio link control (RLC), or packet data convergence protocol (PDCP) layers, and layer 3 (L3) can include a radio resource control (RRC) layer, non-access stratum (NAS), and internet protocol (IP). In an example, the RRC protocol can manage control plane signaling between a wireless device (e.g., a user equipment (UE)) and a radio access network (RAN) via the node (e.g., an eNB).
Reference will now be made to the exemplary embodiments illustrated, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended.